What is relaxin back

Relaxin is a polypeptide hormone belonging to the insulin family. First discovered in 1926 by extracting an impure form from pregnant pigs, since then relaxin has been highly purified in both rats and pigs but a purified human extraction and characterization of its detailed structure is still unknown. Human relaxin-1 (RLN1), relaxin-2 (RLN2) and relaxin-3 (RLN3) are predicted to consist of a two-chain structure and three disulfide bonds in a disposition identical to that of insulin.   Relaxin is capable of activating RXFP1(relaxin/insulin-like family peptide receptor 1)and RXFP2 (relaxin/insulin-like family peptide receptor 2) through the G-protein-coupled receptor. G protein-coupled receptors (GPCRs) are a large protein family of transmembrane receptors that sense molecules outside the cell and activate inside signal transduction pathways and, ultimately, cellular responses. Relaxin is produced mainly by the corpus luteum, in both pregnant and non-pregnant females. During menstruation the body produces relaxin that rises to a peak within approximately 14 days of ovulation and then declines.   In pregnant cycles, rather than subsiding, relaxin secretions continue to rise during the first trimester and then again in the final weeks. In males, relaxin is synthesized in the prostate and released in the seminal fluid.   During pregnancy relaxin has a diverse range of effects, including the production and remodelling of collagen, increase in elasticity and relaxation of muscles, tendons and ligaments. The hormone has both direct and indirect effects that affect the individual person as a whole, affecting almost all parts within the body and can be broken down into the following: Striated and smooth muscles. Central nervous and autonomic nervous systems. Connective tissues in the form of skin, ligament, tendon and cartilage. The cardiac muscles. A systemic deficit of the hormone relaxin and poor inability to utilize the existing hormone produced by the body, contributes to muscle discomfort, occasional bowel and bladder upset, digestive difficulties, dizziness, shortness of breath, aching joints, fatigue, headaches and emotional distress in some women. Being on the contraceptive pill reduces the relaxin levels. It can be suggested that use of hormonal contraceptives before the first pregnancy may cause an increased risk of pregnancy-related pelvic pain in the first pregnancy.(6) High levels of relaxin are also found in pregnant women with Type 1 diabetes as well as twin pregnancies (18)   Correlation between the concentration of the pregnancy hormone relaxin and the stability of the hip joint in newborns indicate that hip instability frequently occurs with decreasing relaxin concentration.(19)

The Functions of Relaxin (20) back

Promotes dilation of blood vessels in several organs and tissues, including the uterus, the mammary gland and the heart. Has a chronotropic action on the heart, has recently been identified in the heart atria. Influences the secretion of hormones by the pituitary gland. Contributes to the regulation of fluid balance. Use of recombinant relaxin in the treatment of systemic sclerosis or scleroderma. Influence renal vasodilation.

Relaxin During pregnancy back

During pregnancy the hormone relaxin influences such things as: The induction of collagen remodelling and consequent softening of the tissues of the birth canal in view of delivery by cervical ripening and rupture of the fetal membranes at term. The inhibition of uterine contractile activity to prevent preterm labour. The stimulation of growth and differentiation of the mammary gland allowing nipple growth to occur. Relaxin plays a role in sperm motility, fertilization, implantation, uterine growth and accommodation; relaxin is needed to support the establishment and maintenance of early pregnancy. Relaxin affects collagen metabolism (chemical processes occurring within a living cell that is necessary for the maintenance of life), inhibiting collagen synthesis (prevent or decrease a period in the cell cycle) and increasing matrix metalloproteinase's (degrade extracellular matrix) that increases collagenase production (collagenase involves enzymes that break down the native collagen that holds animal tissues together).   Although relaxin's main cellular action in pregnancy is to remodel collagen by biosynthesis thus facilitating the changes of connective tissue, it does not seem to generate musculoskeletal problems. High levels of cortisol, estradiol, progesterone and relaxin as well as a significant distention of the symphyseal joint during pregnancy is not a good indicator of pelvic girdle pain.   There is no correlation between age, culture, nationality and numbers of pregnancies that determine a higher incidence of pelvic girdle pain. (5) However, if you experience pelvic girdle pain in one pregnancy you are more likely to experience it in subsequent pregnancies; but the severity can not be determined. Concentrations of relaxin during the two days immediately preceding parturition are significantly greater than all other days. After this time period relaxin is no longer manufactured in large amounts in the postnatal period. The effects of the hormones on the ligaments are still evident until about five months post birth.

Serum relaxin levels were not associated with the degree of symphyseal distention or with pelvic girdle pain in pregnancy.

Estrogen back

Estrogen (also oestrone) is an estrogenic hormone secreted by the ovary. Estrogens are steroids. Estrogen is one of the three estrogens, which also include estriol and estradiol. Estrogen is the least prevalent of the three hormones, estradiol being prevalent almost always in a female body; estriol being prevalent primarily during pregnancy. Functions of Estradiol Breast development and maintenance, adding fat to breasts, hips, thighs during puberty. Improving bone strength and density and accelerating bone maturation and bringing epiphyses to closure, completing growth. Growth of the uterus and development of the endometrial lining to a thickness necessary to support pregnancy and menstruation. Thinning of cervical mucus at ovulation. Promoting and maintaining vaginal mucosal thickness and secretions. Serving as the primary feedback to the brain of sex hormone levels in both males and females. Participating in triggering ovulation and preservation of egg cells. Vascular and cerebral effects.

Estrogen During Pregnancy  back

Triggers the maturation of reproductive organs. Help in the development of sexual characteristics. Contributes to the increase in breast size and assists in the lactation process. Regulates bone density in a foetus. Maintains the endometrium during pregnancy. This increase in the depth and consistency of the uterine lining prepares it for implantation. Estrogen is also responsible for skin changes. Maintains, regulates and triggers the production of other hormones. Estrogen, along with the hormone relaxin, alters pelvic joints and ligaments, and increases mobility of nipple tissue. In late pregnancy, fibers of the cervix are swollen and loosely connected to each other. This is the “ripening” that prepares the cervix to dilate. Protects female foetuses from the effects of androgens in the mother's system. (Androgens are substances that have a masculinising effect). Estrogen is responsible for an increased blood supply and effects the lymphatic's and nerve supply to the uterus, and throughout the body. Another function of estrogen is changes in the character of tissue.

Glucosamine back

Glucosamine is an amino sugar synthesized in the body, and is a component of proteoglycan, which is a major structural component of cartilage. Glucosamine Sulfate is an artificially synthesized salt of Glucosamine. Chondroitin Sulfate is composed of repeating units of glucosamine with attached sugar molecules. Combinations of Glucosamine and Chondroitin have been tried in the treatment of osteoarthritis.

Collagen back

One of the functions of relaxin during pregnancy is to remodel collagen. Collagen is found in all animals and is the most abundant proteins in the human body. Collagen has insoluble, extracellular glycoprotein's with carbohydrate attached to them. The carbohydrate consists of short, usually branched, chains of sugars and nitrogen-containing amino sugars. One of the mechanisms involved in the regulation of collagen production is G-protein linked signal transduction (a process by which a cell converts one kind of signal which involves an ordered sequences of biochemical reactions inside the cell.   Collagen is a fibrous protein occurring in bone, cartilage, muscle, connective tissues and, tendons. In the skin, collagen provides texture, resilience, and shape. In joints, it protects and stimulates anabolic restoration of joint cartilage and synovial fluid and connective tissue. It is a major structural protein in tissues around which cells live and function. There is no organ or tissue which does not have collagen. Bones and teeth are made by adding mineral crystals to collagen. It is a natural protein that provides structural support and is found in skin It is the most abundant protein in your body, and is necessary for the proper functioning of joints, the production of lean muscle tissue, and smooth, supple skin, and the growth of hair and nail. During pregnancy Type's l, 2, 3, 5 and 6 are understood to have a significant role.

Chart of Collagen Types 1 to 12 of 28 back

Type 1 Most abundant in the human body. It is in scar tissue as it repairs. It is found in tendons and the organic part of bone. Type 2 Articular cartilage: the translucent cartilage found at the ends of long bones, also called hyaline cartilage. Type 3 Forms skin, muscle. This collagen is produced quickly by young fibroblasts before the tougher Type I collagen is synthesized. Type 4 Basal lamina; eye lens. Also serves as part of the filtration system in capillaries and the glomeruli of nephron in the kidney. Type 5 Most interstitial tissue (situated between the cells of a structure), associated with Type I and with the placenta. Type 6 Epithelium is a tissue that covers a surface or lines a cavity. Type 7 Some endothelial cells which are thin cells that line the heart, blood vessels, lymphatics, and serous cavities. Type 8 Found in cartilage, also associated with Type 2. Type 9 A type of collagen which is also a proteoglycan. Type 10 Hypertrophic (abnormal enlargement of a part or organ), and mineralizing cartilage. Type 11 Cartilage Type 12 FACIT collagen, interacts with type I containing fibrils, decorin and glucosaminoglycans

Cell back

The word cell comes from the Latin cella meaning, "a small room". The cell is the structural and functional unit of all living organisms. A cell wall is a more or less solid layer surrounding a cell. The cell wall's main purpose is to actually protect the interior from any physical movement that may damage the cell. Osmosis is important because it provides the primary means by which water is transported into and out of cells. The function of osmosis is to diffuse fluid through a semi permeable membrane from a solution with a low solute concentration to a solution with a higher solute concentration until there is an equal concentration of fluid on both sides of the membrane, this flow will slow and finally stop as the pressure becomes such that the diffusion in each direction is equal.

Bone back

Bone has an internal mesh-like structure, the density of which may vary at different points. Bone can be either compact or cancellous (spongy) During the first and second trimester of pregnancy bone remodelling is uncoupled. Serum calcium decreases as bone resorption peaks in late pregnancy. There are significant decreases in bone mineral density at sites rich in trabecular bone, such as the lumbar spine and the trochanter. (21)   Bone cells include: osteoblasts, osteocytes and osteoclasts. Osteoclasts Osteoclasts are large cells that dissolve the bone. They are found on the surface of the bone mineral next to the dissolving bone.   Osteocytes Osteocytes are cells inside the bone. They also come from osteoblasts. Some of the osteoblasts turn into osteocytes while the new bone is being formed, and the osteocytes then get surrounded by new bone. These cells can sense pressures or cracks in the bone and help to direct where osteoclasts will dissolve the bone.   Osteoblasts Osteoblasts are the cells that form new bone. They also come from the bone marrow and are related to structural cells. Osteoblasts work in teams to build bone. They produce new bone called "osteoid" which is made of bone collagen and other protein. Then they control calcium and mineral deposition. They are found on the surface of the new bone.